Ionic dependence of sodium currents in squid axons analyzed in terms of specific ion “channel” interactions (original) (raw)

Abstract

Inward sodium currents were measured from voltage-clamped giant axons externally perfused with artificial seawater (ASW) solutions containing various concentrations of sodium and potassium ions. The data was analyzed under the assumption that under a constant membrane potential sodium conductance is determined by a specific ion-channel site (SIS) reaction. The sodium current density values were expressed in terms of SIS-reaction rates which were compared, by means of minimization techniques, with those computed for various saturation reaction mechanisms. The following conclusions were drawn:

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